Not that I can personally confirm this, being a guy and all, but the new Under Armour running shoe feels like a bra. Which seems logical, considering it was manufactured in a bra factory using bra-making techniques.

Yeah, it's a bit of a departure from the traditional process of manufacturing running shoes.

The new UA Speedform RC ($120) hits the market in early July, but the process of designing the shoe and its “seamless heel cup” started three years ago when UA, which was in the middle of a major push into the bra segment, realized that common bra-making techniques might yield a better-fitting sneaker. Explains Dave Dombrow, senior creative director for UA footwear, "The project started with leaving footwear manufacturing behind.”

As the UA designers started researching apparel-making processes, they observed how bras were the result of precision manufacturing, with laser sighting and sonic welding used to seamlessly bond layers together. Traditional shoemaking involves the use of a last, or a model of a foot, around which the footwear is assembled. But it was impossible to create the key element of the Speedform kicks, their bra-like heel cup, using those methods.

Instead, UA is taking two pieces of proprietary stretch fabric and ultrasonically "welding" them: First they compress them in the desired position, and then zap them with acoustic vibrations to merge the molds. What results from the anatomic 3-D manufacturing process is a heel cup that feels like a sock hugging your foot.

“The idea you wouldn’t use a last is foreign to people,” Dombrow says. “I am biased, but I don’t want to understate the effect of an anatomical heel cup. There are zero distractions and you really have a glovelike sensation for your foot.”

Oddly, the sonic welding idea isn’t anything new, as apparel companies have been doing it in high-end gear—running or otherwise—for years. But most footwear factories simply don’t have the molding techniques or sonic taping machines. Bra factories, though, have them aplenty. It just took Under Armour a moment to realize the potential that existed within that house they're so hellbent on protecting.
Tim Newcomb covers stadiums, design, and technology for SI. Follow him on Twitter at @tdnewcomb.

More Extra Mustard

We've Got Apps Too

Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide - from Peter King, Tom Verducci, Lee Jenkins, Seth Davis, and more - delivered straight to you, along with up-to-the-minute news and live scores.